The ultra-diffuse galaxy GAMA 526784 appears as a tenuous patch of light in this image from the NASA/ESA Hubble Space Telescope. This wispy object resides in the constellation Hydra. It is roughly four billion light-years from Earth. Ultra-diffuse galaxies such as GAMA 526784 have a number of peculiarities.
They can have either very low or high amounts of dark matter. The invisible substance is thought to make up the majority of matter in the universe. Observations of ultra-diffuse galaxies found some with an almost complete lack of dark matter. Other consist of almost nothing but dark matter. Another oddity of this class of galaxies is their unusual abundance of bright globular clusters. It is not something observed in other types of galaxies.
Hubble captured GAMA 526784 with the Advanced Camera for Surveys (ACS). It was installed in 2002 by astronauts during Hubble Servicing Mission 3B. The instrument has played a pivotal role in some of Hubble’s most impressive scientific results.
This includes capturing the Hubble Ultra Deep Field. The ACS has also photographed Pluto in advance of the New Horizon mission. It observed gargantuan gravitational lenses and found fully formed galaxies in the early universe.
This image comes from a set of Hubble observations designed to shed light on the properties of ultra-diffuse galaxies. Hubble’s keen vision allowed astronomers to study GAMA 526784 in high resolution at ultraviolet wavelengths. It helped to gauge the sizes and ages of the compact star-forming regions studying the galaxy.